Short answer
HubSpot's KB: install the HubSpot Sales Office 365 add-in if your mailbox is hosted on Microsoft 365, whether you use Outlook for Mac, Windows or the web. Other providers can't use it, even in Outlook. The Outlook desktop add-in is in maintenance mode. Don't install both on one device.
1. Log and track settings
Settings that affect the extension in my demo portal.

2. Gmail
See the sales extension.